Deferential dialogues between the Court of Justice and domestic courts regarding the compatibility of the EU Data Retention Directive with (higher?) national fundamental rights standards

This article examines the nature, purpose and effect of constitutional dialogues between the Court of Justice of the European Union and constitutional courts taking as example the difficulty encountered in the implementation of the 2006 Data Retention Directive in several Member States. The cooperative relationship, called “deference”, is based on the autonomy and voluntary willingness of national courts to ask for a preliminary ruling by the Court of Justice. Avenues of “silent” dialogue, as happens when constitutional courts do not send for a preliminary ruling while still following the Court’s precedents, are also explored. The case-law where constitutional courts exercised their competence to indirectly review the validity of EU legislation is discussed in light of the constitutional pluralism paradigm. Finally, in the particular field of personal data retention, the judicial activism of the Luxembourg Court in upholding the validity of EU legislation is heavily criticized in light of the protection of fundamental rights. For the judicial dialogue to function properly, both the Court of Justice and constitutional courts should show “deference” to each other's sensitivities in light of the principle of loyal cooperation entrenched in the EU Treaties.